Multiple Measures of Fixation on Social Content in Infancy: Evidence for a Single Social Cognitive Construct?

The preference of infants to fixate on social information in a stimulus is well known. We examine how this preference manifests across a series of free‐viewing tasks using different stimulus types. Participants were thirty typically developing infants. We measured eye movements when viewing isolated faces, faces alongside objects in a grid, and faces naturally presented in photographed scenes. In each task, infants fixated social content for longer than nonsocial content. Social preference scores representing distribution of fixation to social versus general image content were highly correlated and thus combined into a single composite measure, which was independent of demographic and behavioral measures. We infer that multiple eye‐tracking tasks can be used to generate a composite measure of social preference in infancy. This approach may prove useful in the early characterization of developmental disabilities.     

Further remarks on estimating the parameter of a noncentral chi-square distribution

Perlman and Rasmussen (1975) have found estimators of the non-centrality parameter of a noncentral chi-square distribution which have lower mean square error than the maximum likelihood estimator. This paper studies some extensions of their estimators and some related problems.     

Bayesian analysis of reliability in multicomponent stress-strength models

This paper provides a Bayesian treatment of the problem of inference about the reliability of a multicomponent stress-strength system which functions if s or more of k identical components simultaneously operate. All stresses and strengths are assumed to be independent, exponentially distributed random variables. Exact and approximate asymptotic posterior distributions for the reliability are derived, and the results are illustrated by a numerical example.     

Effects of inspection errors on curiailed dorman-type procedures

The effects of inspection error on a two-stage procedure for identification of defective units is studied. The first stage is intended to provide the number of defective units in a group of n units; the second stage consists of individual inspection until the status of all units is (apparently) established     

Bayesian assessment of assumptions of regression analysis

Many statistical procedures are based on the models which specify the conditions under which the data are generated. Many applications of linear regression, for example, assume that:(i) the observations are independent; (ii) the errors in the observations are identically distributed; (iii) each error has a normal distribution with mean zero and unknown variance σ²> 0. Previous works have examined individual departures from these assumptions. Here we examine composite departures. It is assumed that the error distribution in a linear model is power-exponential and that the observations are generated via a first order autoregressive model with the possibility of spurious observations. The consequences are illustrated via an example.     

Applied regression analysis bibliography update 1990-91

The 25-page Bibliography in Applied Regression Analysis, 2nd edition, by N.R. Draper and H. Smith, published by Wiley in 1981, was previously extended by a list of selected references available during 1988-89, plus a few older references. See Communications in Statistics - Theory and Methods, 19(4), 1205-1229 (1990). Here is a further update covering the years 1990-91, and following the same format. As before, items were chosen on the basis of their perceived relevance to practical applications (sometimes rather widely interpreted). The classification system used is that of the book.

The references were selected mostly from the issues of these journals: Annals of Statistics; Applied Statistics; Biometrika; Canadian Journal of Statistics; Bulletin of the International Statistical Institute; Journal of the American Statistical Association; Journal of Quality Technology; Journal of the Royal Statistical Society, Series A and B; and Technometrics.     

Projecting future utilization of medically assisted fertility treatments

This study estimates the future utilization of medically assisted fertility treatments in Australia, focusing on assisted reproductive technologies (ARTs), intrauterine insemination (IUI), and ovulation induction. A multistate cohort component population projection model is used to determine future fertility rates from 2016 to 2026 by age and education level. These are combined with information on recent trends in use and success rates to indirectly estimate future age-specific probabilities of fertility treatment utilization. The number of ART cycles is expected to increase by 61 per cent between 2016 and 2026 if treatment success rates remain at 2015 levels, or by 34 per cent if recent improvements in ART success rates continue. The model also predicts that numbers of IUI cycles and ovulation induction cycles will decrease by 17 and 3 per cent, respectively. This research confirms the importance of including both technological improvements and socio-demographic changes when predicting future fertility treatment utilization.